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In recent years, the COVID-19 pandemic has had a huge influence on all societies across the world, including the availability and new developments within the ophthalmology field. Fortunately, most societies and countries are back on track with the normalization of healthcare activities. In addition, companies are now introducing and marketing new technologies to be implemented clinically. Within the corneal refractive surgical field, the major area of interest in the past decade has been the evaluation of small-incision lenticule extraction (SMILE®) compared with the well-known successful LASIK surgical technique. My interest in the SMILE technique started in January 2010 when I visited Dr. Rupal Shah in Vadodara, India. Returning to Denmark, we started with femtosecond lenticule extraction and soon after with SMILE®. Until now, the SMILE® technique has only been commercialized for the treatment of myopia and myopic astigmatism. Although the surgical procedure is quite different from LASIK, the two methods seem to perform similarly well concerning efficacy, predictability, and safety.1 Only one SMILE® femtosecond laser, the VisuMax produced by Carl Zeiss Meditec, was available for 10 years, but now several other lasers have been developed, tested, and marketed. “CLEAR,” “SmartSight,” and “SILK” are now the brand name for these new procedures as “SMILE®” is a registered trademark by Carl Zeiss Meditec. Therefore, we need to use a new collective name for these techniques: Refractive lenticule extraction. The companies behind each of the new femtosecond lasers designed for refractive lenticule extraction use these new “catchy” names for their technique. Ziemer has further developed its FEMTO LDV Z8 into the FEMTO Z8 NEO and has named the procedure “CLEAR®” (Corneal Lenticule Extraction for Advanced Refractive Correction). Schwind has introduced its ATOS femtosecond laser and calls its procedure “SmartSight®.” Finally, Johnson and Johnson has developed the ELITA femtosecond laser and named its procedure “SILK®” (Smooth Incision Lenticule Keratomileusis). Carl Zeiss Meditec also marketed their new femtosecond laser VISUMAX 800, and the procedure performed with this laser is called “SMILE® pro.” By the end of 2023, more than 700 papers on refractive lenticule extraction have been published (PubMed search). Almost all are studies based on the SMILE® technique performed with the VisuMax femtosecond laser. The coming years will show how the new femtosecond lasers perform and whether lenticule extraction will finally become safe and effective and marketed for hyperopia treatments. I do not think we will see many randomized controlled trials comparing one femtosecond laser with another. The investment for refractive eye clinics is simply too large to invest in two different femtosecond lasers and run such studies with the many expenses related to GCP monitoring, etc. Although the short-term safety of corneal refractive laser surgery is excellent, the subsequent development of ectasia after surgery has major implications for the patient. For more than 20 years, it has been known that patients may develop ectasia after LASIK, but with SMILE® based on a cap rather than a flap, it was hoped that ectasia development would be eliminated. Unfortunately, this is not the case.2 Ectasia can occur also after SMILE®; thus, the same preoperative precautions as before LASIK should be taken before surgery is planned. For patients developing ectasia after refractive surgery, corneal crosslinking (CXL) is fortunately an option, and the continuous development of the technique may eventually end up with an efficient option for an epithelium-on procedure. The iontophoresis principle has, however, recently been found inferior to standard CXL3 but may be improved, and new developments in penetration enhancers may allow the patient to avoid pain and slow visual recovery after the standard epithelial-off CXL.4 In refractive surgery, simultaneous SMILE® surgery and CXL, named SMILE Xtra, seem to reduce the already low incidence of ectasia further.2 One of the most hyped publications in 2023 was a study on implantation cell-free engineered corneal tissue, a bioengineered porcine construct, double crosslinked in a stromal pocket for treatment of keratoconus.5 In this pilot feasibility study, the authors concluded that their work demonstrated restoration of vision by using an approach that is potentially equally effective, safer, simpler, and more broadly available than donor cornea transplantation. The principle of human corneal lenticule implantation for keratoconus treatment has been reported previously with mixed results.6 Further developments in the construction of corneal tissue implants without the need for human corneal tissue may, however, have great potential. Intraocular refractive procedures include refractive lens exchange (RLE) and implantations of phakic intraocular lenses (PIOLs). A common indication for RLE is presbyopia correction, and in recent years, many types of IOLs have been introduced on the market. The traditional trifocal IOLs and diffractive continuous-range-of-vision IOLs provide typically good distance, intermediate, and near visual outcomes, but patients should be advised of the likelihood of visual disturbances, particularly halos. Comprehensive patient selection and examination, combined with the knowledge of the most recent options and adequate patient counseling, including neuroadaptation, are all very important aspects to avoid patient dissatisfaction.7 Another well-known but often ignored fact is the lifelong increased risk for retinal detachment after the removal of the natural crystalline lens. The risk after phacoemulsification is approximately ten times the general population’s risk for rhegmatogenous retinal detachment.8 In Denmark, the development of rhegmatogenous retinal detachment up to several years after cataract surgery or RLE is considered a direct complication related to the primary procedure, and the patient thus qualifies for financial compensation. Implantation of PIOLs is increasingly considered a promising refractive surgery alternative to laser vision correction. One factor may be that it is easy to implement PIOLs in a conventional practice with existing cataract surgical functions as no expensive excimer or femtosecond laser is needed. A recent meta-analysis concluded that phakic intraocular lens implantation using an implantable collamer lens (ICL) with a central port had excellent efficacy, safety, and patient outcomes.9 The average follow-up in the studies was, however, only around 2 years. The normal age-related changes in the natural lens will, inevitably, increase the risk for cataract as the space between the posterior chamber PIOL and the natural lens reduces, and cataract formation will possibly occur earlier. An excellent review on PIOLs in this journal10 underlines the need for long-term follow-up of patients undergoing this type of surgery. The risk of increased endothelial cell loss over the years after the implantation of iris-fixated PIOLs results in corneal decompensation in some patients, although the actual incidence is unknown. Before surgery, the patients need to be informed of this risk. The year 2023 provided increased focus on artificial intelligence (AI) with the introduction of ChatGPT, which can provide answers to many questions, write essays on whatever topic, and perform many other tasks. It has created a big debate whether the source should be allowed in schools and universities, but AI also provides great opportunities for refining many manual tasks. One example is the program “Be My Eyes,”11 which connects people needing sighted support with volunteers and companies through live video around the world. Right now, the company is trying to develop AI-powered visual assistance such that visually impaired people can use their mobile smartphone to “see” objects and tell the visually impaired what is on the image. All AI solutions need to be trained and with the assistance of volunteers around the world, confirming or correcting the AI interpretation of an image. “Be My Eyes” may become a very useful tool. Getting back to the global perspective after COVID-19, cataract is still the second most common cause of low visual acuity after lack of refractive correction. However, what has happened over the two last decades since VISION 2020 was initiated? What was VISION 2020? VISION 2020: The Right to Sight was launched in 1999 by the World Health Organization and the International Agency for the Prevention of Blindness. It sought to promote “A world in which nobody is needlessly visually impaired, where those with unavoidable vision loss can achieve their full potential.” The Global Initiative was set up to “Intensify and accelerate prevention of blindness activities to achieve the goal of eliminating avoidable blindness by 2020.” It sought to do this by “Focusing initially on certain diseases which are the main causes of blindness and for which proven cost-effective interventions are available.” The achievements and lasting effects of VISION 2020 were summarized by Gullapalli N Rao, LV Prasad Eye Institute, Hyderabad, India.12 In the report, certain global contributors were highlighted; the Australian, the United States, and the UK Agencies for International Development, and the German, Canadian, French, and Danish government’s support. A few national contributors were highlighted as well: India: The Indian government has always provided significant funding to the prevention of blindness programs through the National Program for the Control of Blindness (NPCB) established in 1976. During the last two decades, this national funding quadrupled and has reshaped the way eye care is delivered in the country, resulting in a positive impact on millions of lives. The biggest success story is the rapid escalation of cataract surgical volume. Dr. Rao concluded: The Vision Loss Expert Group published its report in 2017 from the data of 2015. According to this report, 253 million in the world are visually impaired, of whom 36 million are blind. Despite the significant demographic shift in the past two decades, there has been a decline in the prevalence of visual impairment from 4.58% in 1990 to 3.38% in 2015. Disparities due to socioeconomic status, geography, and gender remain. This is an indication that “equity“ in eye care remains elusive. Universal Eye Health providing comprehensive eye care equitably to everyone should be the focus for the immediate future. Through this, there is an opportunity for this sector to create a model for comprehensive “Universal Health Care,” an aspiration of many countries. In conclusion, refractive and cataract surgery have never been better and safer than today. With millions of people around the world in need of treatment, the ophthalmological field has a large assignment ahead. In addition, increasing demands and welfare in many countries expand the pressure on ophthalmic surgeons to provide a spectacle-free life for millions of citizens. Continued research in improving ophthalmic care and efficacy is essential. Disclosures Aarhus University has signed consultancy agreements on behalf of Jesper Hjortdal with: Carl Zeiss Meditec, Jena, Germany Kowa Pharmaceutical Europe, Zurich, Switzerland Novo Nordisk, Denmark.
Jesper Hjortdal (Fri,) studied this question.